POS0975 COMPARISON OF CLINICAL AND DEMOGRAPHIC FINDINGS OF PATIENTS DIAGNOSED AS WITH FULL SPINAL FUSION AND WITHOUT ANY SPINE DAMAGE
Authors: C. Yörük, S. Gulle, İ. Sari, F. Onen, A. Balci
Journal: Annals of the Rheumatic Diseases (2022)

Background Erosions and sclerosis are early manifestations of radiographic progression, which can form syndesmophytes that bridge between the vertebrae and eventually lead to spinal fusion or the characteristic bamboo spine appearance in some patients.Bridging syndesmophytes in the spinal column plays a key role in the progression of AS. 1 The development of ankylosis in the axial skeleton is considered to be the most important long-term outcome parameter for axial pondyloarthritis (axSpA). 2 Objectives In this study, we aimed to evaluate patients with ankylosing spondylitis (AS) diagnosed with grade 4 sacroiliitis followed in our rheumatology clinic, without spinal column involvement and with complete spinal ankylosis (bamboo vertebra), together with their clinical, demographic and laboratory findings. Methods A total of 202 patients with unilateral/bilateral grade 4 sacroiliitis, who were registered in the Dokuz Eylul University Hospital data system, diagnosed with AS according to the modified New York criteria, were included in the study. Cervical, dorsal and lumbar radiographs of all patients were evaluated for structural damage, in addition to lateral and anteroposterior aspects, as well as posterior and facet joint involvement. In the study, all radiographs were evaluated twice at separate times. Results It was found that 19 (9.5%) patients had no involvement of the spinal column and 19 (9.5%) had spinal fusion appearance. It was determined that patients with spinal fusion were older (p&lt;0.001) and the frequency of male gender was higher (p=0.042) than patients without any spinal involvement.(Table 1) In multivariate analysis; ≥45 years old [OR: 10.5, CI: 95%, 2.8-39.2; (p&lt;0.001)] and male patients [OR: 10.5, CI: 95%, 1.14-96.56; (p=0.042)] was found to have an increased risk for the development of spinal fusion. TNFi retention rates (78.9% vs. 52.6%), TNF switch rates (53.3% vs. 45.5%) and TNF type distributions were similar in both groups (p&gt;0.05).There was no significant difference between the patients with complete spinal fusion and no spinal involvement in terms of right and left hip BASRI scores (p&gt;0.05). Table 1. Demographics Spinal Involvement (-) (n=19 ) Full Spinal Involvement (+) (n=19 ) p n (% ) n (% ) Age &lt;0.001 ≤45 17 (89.5) 0 (0) AUC (SH.): 0.945 (0.040 ) &gt;45 2 (10.5) 19 (100) 10.5 (2.8-39.2 ) OO Sex (Erkek ) 12 (63.1) 18 (94.7 ) 0.042 10.5 (1.14-96.56 ) OO CRP 11 (57.9) 12 (63.2) 0.999 HLA-B27 10 (64.3) 9 (60.0) 0.831 Psoriasis 1 (5.2) 1 (5.3) - Family History 4 (21) 0 (0) - Alcohol 1 (5.2) 2 (10.5) - Cigarette 7 (36.8) 4 (21.1) 0.475 Dactylitis 1 (5.2) 0 (0) - Enthesitis 0 (0) 1 (5.3) - Uveitis 3 (15.7) 4 (21.1) 0.234 IBD 3 (15.7) 0 (0) - HT 1 (5.2) 7 (36.8) 0.044 DM 1 (5.2) 5 (26.3) 0.182 CHD 0 (0) 2 (10.5) - Aortic Failure 1 (5.2) 0 (0) - Mann-Whitney U Test (Monte Carlo), ROC (Receiver Operating Curve) Analysis (Honley&amp;Mc Nell - Youden index J); AUC: Area under the ROC curve; OR: Odds Ratio; RC: ROC Curve Analyze, IBD: Inflammatory Bowel Disease, HT: H ypertension, DM: Diabetes Mellitus, CHD: Coronary Heart Disease, CRP: C-Reaktif Protein, n: Number, %: Percent Conclusion In our study, we reached four important clinical results: (1) Spinal fusion was observed in 9.5% of the patients with bilateral Grade 4 sacroiliitis diagnosed with AS, 9.5% had no spinal involvement and 81% had varying degrees of spinal injury. (2) Anti-TNF treatment responses were similar in patients with spinal fusion and no spinal involvement. (3) Except for being &gt;45 years old and having a male gender, no other factor was found to predict the development of spinal fusion. (4) There was no difference in the degree of hip involvement between patients with complete spinal fusion and no spinal involvement. References [1]Siré E Van Der Heijde, D. et al. Modified stoke ankylosing spondylitis spinal score as an outcome measure to assess the impact of treatment on structural progression in ankylosing spondylitis. [2]Ramiro, S. et al. Spinal radiographic progression in early axial Spondyloarthritis: Five-year results from the DESIR cohort. Arthritis Care Res. (Hoboken). 71 , 1678–1684 (2019). Disclosure of Interests None declared